Saturable and Decoupled Constant-Parameter VBR Model for Six-Phase Synchronous Machines in State-Variable Simulation Programs

Six-phase electrical machines are often found in special purpose applications, such as vehicular, ship, and aircraft power systems, and are now becoming considered in renewable energy generation. For design and analysis of such power systems, accurate and numerically efficient models are required for various transient simulation programs. Recently, a constant-parameter voltage-behind-reactance (CPVBR) model has been developed for magnetically linear six-phase synchronous machines as an alternative to the conventional qd0 and VBR machine models. In this paper, a saturable CPVBR model is presented for six-phase machines, which includes the main flux saturation and achieves magnetically decoupled and constant RL interfacing branches. The new magnetically decoupled CPVBR (DCPVBR) model has many advantages for implementation in commonly available simulation programs where it can be easily interfaced with inductive and/or power-electronic circuit elements. The proposed DCPVBR model is demonstrated to have improved computational performance compared to the conventional qd0 and VBR models.